Perspectives on prediction: Does third-person imagery improve task completion estimates?

People typically underestimate the time necessary to complete their tasks. According to the planning fallacy model of optimistic time predictions, this underestimation occurs because people focus on developing a specific plan for the current task and neglect the implications of past failures to meet similar deadlines. We extend the classic planning fallacy model by proposing that a phenomenal quality of mental imagery – the visual perspective that is adopted – may moderate the optimistic prediction bias. Consistent with this proposal, participants in four studies predicted longer completion times, and thus were less prone to bias, when they imagined an upcoming task from the third-person rather than first-person perspective. Third-person imagery reduced people’s focus on optimistic plans, increased their focus on potential obstacles, and decreased the impact of task-relevant motives on prediction. The findings suggest that third-person imagery helps individuals generate more realistic predictions by reducing cognitive and motivational processes that typically contribute to bias.

► Students underestimated how long they would take to finish upcoming tasks.
► The optimistic prediction bias was reduced by adopting a third-person perspective.
► Third-person imagery increased predictors’ focus on obstacles.
► Third-person imagery reduced the biasing effects of motivation on prediction.